In an optical imprint, an imprint mold is pressed into a transfer layer made of a light curing resin, and a pattern is transferred by separating the imprint mold from the transfer layer cured by irradiation of an ultraviolet (UV) light from a rear surface side of the imprint mold.
In manufacturing of a micro-electromechanical system (MEMS) device, a semiconductor device or the like, for example, patterns are formed on a plurality of transfer areas provided on a surface of a substrate, such as silicon (Si) and the like. In this case, the patterns are continuously transferred in a step-and-repeat manner by moving the imprint mold or the substrate in longitudinal and transverse (XY) directions.
Also, in manufacturing of an optical part, such as a micro lens, a diffraction grating and the like, for example, a pattern is formed on a surface of a windable substrate, such as a resin film and the like. In this case, the pattern is transferred while the substrate is sequentially rolled up onto a roll.
In the optical imprint, it is necessary to prevent leakage of the irradiation light through a unpatterned region of the imprint mold to the transfer layer. Moreover, since the pattern transferred from the imprint mold is composed of minute concaves and convexes on the surface, it is necessary to prevent adhesion of foreign particles on a surface of the transfer layer.
The imprint mold may be mechanically held with a peripheral area or side surfaces of the imprint mold, or with fixing of a rear surface of the imprint mold, in a mold holder of an imprint tool. When the transfer layer is cured, a portion of the transfer layer, which is located in the vicinity of a target transfer area, may be also cured by the light transmitted through the unpatterned region around the pattern region of the imprint mold. It is impossible to transfer a pattern to the cured portion of the transfer layer. For this reason, a width of boundary area between the transfer areas adjacent to each other may become larger than necessary.
For example, there is a technique for forming an light shielding film in a region other than the pattern region of the imprint mold and preventing curing of the transfer layer other than the target transfer area (refer to JP-A 2007-19466 (KOKAI)). However, when a part of the light shielding film is held so as to be in contact with the mold holder of the imprint tool, there is a fear in that the foreign particles, generated from the light shielding film due to a mechanical external force when transfer is repeated or when the imprint mold puts on to the imprint tool or takes off from the imprint tool, adhere on the transfer layer directly or through adhesion to the mold holder. When the light shielding film is not formed on a portion held by the mold holder in order to prevent generation of the foreign particles, the irradiation light may leak from a gap between the mold holder and the light shielding film.